High functionality, low melt viscosity, flakable solid epoxy resin with good heat resistance

ABSTRACT

Liquid epoxy resins can be converted to non-sintering, relatively low equivalent weight, flakable solid opoxides having relatively low melt viscosities by advancing the resins with 1,1,1-tri(hydroxyphenyl)alkanes or -alkenes in which the alkane or alkene moiety contains from 1 to 11 carbons.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation of application Ser. No. 663,295, filed Oct. 22,1984.

BACKGROUND OF THE INVENTION

The use of epoxy resins as casting resins and molding compounds is wellknown. In such application, the resins desirably have certain of theproperties generally shown by higher molecular weight resins, i.e., arenon-sintering, flakable solids, but also have the lower equivalentweights and low melt viscosities characteristic of lower molecularweight resins. It will be appreciated that resins having such acombination of properties are not easily come by; a compromise isgenerally made.

Conventional expedients include adducting novolacs per se with thediglycidylether of bisphenol A (DGEBA) and the use of ring-substitutedepoxy novolacs, such as--for example--"epoxidized" cresol novolacs. Thenovolac components of such adducts or substituted epoxides consistpredominantly of linear, oligomeric molecules having an average of fromabout 3 to 6 phenolic hydroxyls--as such or as glycidyl ethers thereof.

DGEBA, a low molecular weight diepoxide, is conventionally "advanced" toa higher molecular weight through adduction of oxirane groups withphenolic hydroxyls in novolacs or bisphenols (Bisphenol-A or "bis A",predominantly), thereby producing polyether polyhydroxy epoxides. Theadduction conventionally is carried out in the presence of a catalyst orinitiator constituting about 0.1 wt.% of the reaction mixture.Typically, the epoxide to bisphenol weight ratio is about 3:1 and thephr of the phenol (parts bisphenol per hundred parts of the "resin" orepoxide) is about 100/3×1=33.3. The reactants and catalyst are heatedrapidly to onset of an exotherm, at about 150° C. The exotherm isallowed to drive the temperature to a peak value of about 180°-200° C.and then to subside until the temperature reaches about 160° C. Thistemperature is maintained for about 3 hours and the product is pouredinto trays and allowed to cool and solidify or is "flaked" (cooled andsolidified in the form of chips or flakes).

The resulting advancement products are generally prone to sinter if theyhave softening points of about 60° C. or less.

Not all conventional molding or casting epoxies are solids and, of thosewhich are, not all are flakable and/or non-sintering. That is, theinconveniences involved in using resins which can't be flaked and which"sinter" or "block" (lose particulate form by fusing under their ownweight at ordinary temperatures) are accepted as a trade-off against thehigher costs and/or poorer heat resistances (when cured) of more easilyworked-with resins. Another trade-off against cost is slower gellation.That is, the lower functionality resins, although slower gelling, arealso less expensive and may be acceptable on this account in somespecific applications.

Thus, the ordinary, unsubstituted novolac epoxides have acceptably lowermelt viscosities and relatively high functionalities and glasstransition temperatures (Tg's) but cannot be utilized simply as crudereaction mixtures which have not been worked up (working up costsmoney). They also sinter, by reason of unavoidably including excessiveproportions of low molecular weight species. The solid epoxies obtainedby advancement of DGEBA with bisphenol A can be used simply as fusionmixtures but will have high melt viscosities, low Tg's and lowerfunctionalities when of sufficient average molecular weight to benon-sintering. The substituted novolac expoxides have high Tg's, do notinclude excessive proportions of low molecular weight species and haverelatively high functionalities. However, they cannot be used asreaction mixtures which have not been worked up (to remove solvent,by-products; etc.) and have somewhat high melt viscosities.

A recently developed type of epoxy "novolac" is the oligomeric, highfunctionality epoxides disclosed in U.S. Pat. No. 4,394,496, as beingformed by the adduction of 1,1,1-tri(hydroxyphenyl)alkanes with thecorresponding triglycidyl ethers thereof. These epoxides have high Tg'sand are flakable and non-sintering but also have high melt viscosities,are non-linear and would appear to be useful in epoxy casting or moldingresin systems only in admixture with other types of epoxies.

The monomeric triepoxides also disclosed in the patent include some (thetriepoxide of leucaurin, most notably) which are liquids of lowequivalent weight and--when cured--have high heat distortiontemperatures. However, they are also highly viscous.

OBJECTS OF THE INVENTION

The primary object of the present invention is to provide an epoxy resinhaving utility as a relatively inexpensive, solid molding or castingmaterial which has a low melt viscosity, a high functionality and anadequately high Tg, is both non-sintering and flakable and can beprepared as a fusion mixture which does not require working-up to beready for use.

A further object is to provide such a resin which is derivable by thereaction of known kinds of epoxy resins with polyphenols readilyobtainable as or from by-products of salicyclaldehyde manufacture.

An additional object is to provide as such a resin one in which thepoly-phenol need be present only in such minor amounts that theepoxide/phenol reaction mixture does not prematurely gel at thetemperature required for an adequately low melt viscosity.

Another object is to provide an epoxy molding or casting resin which ispreparable from reactants which can be employed in such low proportionsthat the resin, although a solid, has a relatively low EEW.

An additional object is to provide solid epoxy resins having lowerepoxide equivalent weights than those conventionally employed as moldingcompounds.

A further object is to provide a solid epoxy molding or casting resinwhich can be flaked at lower temperatures and is therefore more stableto processing.

It is also an object to provide an improved advancement process whichmakes practicable the use of 1,1,1-tri(hydroxyphenol)-alkanes or-alkenes, as the phenolic reactant, on a commercial scale.

Still other objects will be made apparent to those knowledgeable in theart by the following specifications and claims.

SUMMARY OF THE INVENTION

It has been found that the foregoing objects can be achieved by meansof:

I. An epoxide having an average oxirane functionality of about 2 or moreand comprising at least 5 weight percent of oligomeric molecules whichare each derivable from adductive reaction of a diepoxide having an EEWof about 300 or less (preferably 170-190) with a1,1,1-tri(hydroxyphenyl)-alkane or alkene wherein the alkene moietycontains from 1 to 11 carbons, the mole ratio of said diepoxide to saidtriphenol, in each of said molecules, being, independently, within therange of from 2:1 to 3:1;

II. Preparing said adduction-derivable molecules by heating from about10 to about 30 parts by weight of the triphenol with one hundred partsof the diepoxide until a melt results, initiating stirring mixture, sansany free diepoxide or triphenol species, i.e., may consist essentiallyof one or more [monomeric or] oligomeric adduction products derived fromthe diepoxide and triphenol. In another option, the epoxide (I) maycomprise not only such adducts (in amounts of at least 5 weightpercent)--with or without free starting epoxide--but may also includeother epoxides, phenolics or adducts of epoxides with monophenols and/orother polyphenols.

Desirably, the epoxide I consists of the mixture obtained by reacting adifunctional liquid epoxy resin with from about 10 to about 30 phr ofthe triphenol and advantageously 16-28 phr thereof. Preferred is themixture obtained when the diepoxide is DGEBA (as such or partiallyhydrolyzed) and from about 18 to about 28 phr of the triphenol isprovided. More preferred are mixtures of the latter type in which thetriphenol is a 1,1,1-tri(hydroxyphenyl)methane. Particularly preferredare such mixtures in which from about 18 to 22 parts of1,1,1-tris(p-hydroxyphenyl)methane is employed as the triphenolcomponent.

Either or both of the diepoxide and triphenol reactants may include oneor more non-interfering substituents, i.e., substituents which do notadversely effect the adduction reaction or the product thereof to anintolerable degree.

The present composition invention embraces both the cured and uncuredforms of the epoxide (I). By the term "cured" is meant converted, bywhatever means, to a sufficiently rigid and insoluble solid to haveutility for some specific purpose.

DETAILED DESCRIPTION

Suitable "diepoxides" for the preparation of the specifiedadduction-derivable molecules comprised in the epoxide composition (I)are polyepoxides having average functionalities of from about 1.8 toabout 2.2 and EEW's of up to about 300.

Exemplary types of such epoxides are diolefin diepoxides,vinylcycloalkene dioxides, dicyclodiolefin dioxides, divnylbenzenedioxide, diallylbenzene dioxide, the dioxide of biscyclopentenyl ether;the dioxide of p,p'-divinyldiphenyl, the dioxides of divinyldiphenylsulfide and -oxide; diglycidyl ether, the diglycidyl ethers ordihydroxy benzenes and dinuclear diphenols ("bisphenols", most notably)and the diglycidyl esters of diacids.

Other representative epoxides are hydantoin epoxides, such as, forexample, N,N'-diglycidyl hydantoins,1-glycidyl-3-(2,3-diglycidyloxy-prop-1-yl)-5,5-dimethylhydantoin and1,3-di-(1-glycidyl-5,5-dimethyl-hydantoin-1-yl)-2-glycidyloxypropane(the latter, nominally trifunctional, epoxides being employed inadmixture with one or more epoxides of lower functionality, such thatthe average functionality of the epoxide reactant is about 2.2 or less).Dihydrouracils, barbituric acids, cyanuric and isocyanuric acidscomprising 2 or 3 glycidyl groups are also suitable.

Any of the foregoing epoxides of course may include such non-interferingsubstituents as it is synthetically feasible to incorporate in them(without unduly increasing their EEW's).

More exotic types of low molecular weight diepoxides, such as thosecontaining silicon, phosphorous or other hetero atoms in linear,branched or cyclic segments of the molecule may also be suitable forpreparation of the predominant component of the epoxide (I), either asthe sole diepoxide employed in the adduction or in admixture with otherdioxides.

The preferred diepoxides are liquid epoxy resins which consist at leastpredominantly of molecules, of the formula ##STR1## wherein the averagevalue of n is within the range of from 0 to about 0.15 and may includeminor proportions of molecules derivable, by oxirane hydrolysis, frommolecules of the latter formula.

For ordinary commercial practice, nominal diepoxides formed by partialhydrolysis of a resin consisting of molecules of the latter formula andhaving an average n value of about 0.15 are most preferred.

Suitable triphenol reactants for the preparation, by adduction, of theessential component of (I) are those of the following formula: ##STR2##wherein R is H or a branched or linear, C₁ -C₁₀ alkyl or alkenylradical, n is 0, 1 or 2; X is any non-interfering substituent, the sameor different in each occurrence and the position of the --OH on the ringmay be the same or different in each occurrence. Desirably, n is zero, Ris an alkyl group of less than 5 carbons and the --OH group is in thesame position in at least two of the three rings. Preferably, R is H.The most preferred triphenol is that in which R is H, n is zero and each--OH is in the para position, i.e., is the trisphenol, leucaurin.

The triphenols of formula (I) may be made by the methods described inthe above-referenced '496 patent.

Another source of tri-(hydroxyphenyl)methanes is the crude reactionmixture produced in the manufacture of salicyclaldehyde by theReimer-Tiemann (R-T) reaction of chloroform with excess phenol in thepresence of NaOH. The R-T reaction mixture is neutralized with HCl,thereby causing separation of an organic phase known as "acid oil" fromwhich the salicyclaldehyde, any unconverted CHCl₃ and most of the phenolcan be removed by steam stripping. The residual "para tar" contains thetriphenols, some phenol and a substantial amount of parahydroxybenzaldehyde--which can be removed by extraction with hot water.The raffinate, or "waste bottoms", contains the monomeric triphenols andcan be utilized in the present invention for epoxide advancement.Alternatively, the para tar may be employed as a lower concentrationtriphenol reactant. Also present in the acid oil, para tar and wastebottoms are substantial amounts of oligomeric polyphenols of the typedisclosed in U.S. Pat. No. 4,390,664.

The polyphenol from which at least 5 weight percent of the epoxidecomposition (I) is adduction-derivable (derived, preferably) is a1,1,1-tri(hydroxyphenyl)alkane or alkene as above defined. However, (I)may include adduction products of other polyphenols with the samediepoxide(s) or with other epoxides (not necessarily difunctional, solong as the average oxirane functionality of (I) is about 2). Preferredamong such other polyphenols are bisphenols; bisphenol-A, most notably.Such other adducts may be coformed with the predominant component--as byreacting a mixture of bis-A and the triphenol with DGEBA, for example,or may be separately prepared and blended with the essentialadduction-derivable (and any other) components. As a general rule,however, the advantages of the present invention will be realized to agreater extent when the weight ratio of the triphenol to the otherpolyphenols comprised in the composition (I) is at least 2:3; desirablythe ratio is at least 1 to 1, preferably at least 10 to 1 and mostpreferably infinite.

Illustrative of higher functionality phenols which may be present (asadducts with epoxides) in (I), at least in minor amounts, are branched,3 to 7 functional, polynuclear polyphenols--such as those disclosed inU.S. Pat. Nos. 2,801,989 and 4,390,664 and consisting of oligomeric,acid-catalyzed condensation products of monohydroxybenzenes withacrolein or monohydroxybenzaldehydes, respectively.

The adduction reaction may be carried out on a laboratory scale ingenerally the same manner in which DGEBA is conventionally advanced withbis-A, except that the epoxide/polyphenol mixture--regardless ofaddition sequence--is not stirred until both reactants are molten;otherwise, very troublesome agglomeration results. However, the latteradaptation does not suffice to make the process practicable with thepresent triphenols on a commercial scale. The higher functionality ofthe triphenol generally tends to cause a relatively greater increase inthe viscosity of the reaction mixture during the post-exotherm period.This is particularly the case when the product is held several hours asa melt for flaking; the last-flaked portion of the melt becomes veryviscous.

It has been found that holding the amount of the advancement catalystemployed to 0.1 phr or less and forced post-exotherm cooling, at leastto flaking temperatures, not only greatly reduces the upward viscositydrift but also permits inclusion of substantially more of the triphenol(28 phr, maximum, versus 24 phr of leucaurin, for example) in theproduct.

In terms of manipulative steps, either version of the process isuncomplicated. The diepoxide(s) and polyphenol(s) are charged to thereactor, preferably as particulate solids but optionally as preformed,separate melts. Once both reactants are in contact with each other in amolten state, stirring is initiated, the catalyst (ethyl triphenylphosphonium acetate or "A-1 catalyst", for example) is added and heatingcontinued at least until the melt reaches (or will reach by "coasting"to) the temperature at which the exotherm starts. Preferably, heating iscontinued until the peak temperature reached is high enough to ensureessentially complete dissolution (and conversion) of all of thetriphenol reactant. This will generally require more heat than isevolved in the exotherm, when the triphenol is leucaurin and/or whenminimal amounts of catalyst are employed. That is, the exothermpreferably is "forced" to a higher peak temperature than would bespontaneously attained.

The reaction mass is cooled, if necessary, to limit the peak temperatureto a preselected value of from about 180°-220° C., preferably 185°-200°C. Thereafter, cooling is so regulated that the time period required toreach a temperature (150° C., for example) suitable for holding andflaking is of a preselected, relatively brief duration (about 1/2 houror less, in general). Thereafter, the product (the reaction mixture) maybe flaked or otherwise processed as a melt, dissolved in a vehicleappropriate to a contemplated use or allowed to solidify.

It is of course possible to carry out the adduction in a mediumconsisting of one or more solvents. Heating will generally be necessaryto effect dissolution of the reactants in a satisfactorily brief timeperiod and, again, it may be necessary to delay agitation until at leastone of the reactants is molten (unless the reactants are dissolvedseparately). Suitable solvents for this purpose are those which areconventionally employed for preparation of high molecular weightDGEBA/Bis-A advancement products. Unless the resulting reaction mixturecan be utilized per se, without removing the solvent(s) from it, thisoption is more costly and less preferred.

In any case, the peak exotherm temperature desirably is allowed to reacha value (200° C., for example) at which the catalyst (A-1, for example)rapidly decomposes. This of course requires, when solvents are employed,the use of high-boiling solvents or operation at super-atmosphericpressures.

The relative amounts of the diepoxide and the triphenol charged to theadduction reaction are such that at least four oxiranes are provided foreach phenolic hydroxyl present in the charged triphenol.

Ordinarily, the oxirane to phenolic --OH ratio will be at least as highas that corresponding to a contemplated minimum triphenol content ofabout 10 phr. If it is desired to maximize the content of lowermolecular weight adducts in the product, even higher epoxide totriphenol ratios will be required.

The following considerations show that the average number of diepoxidemolecules per triphenol molecule in the adduct molecules necessarilywill be within the range of from about 2:1 to 3:1. That is, in thesimplest such adduct having only two oxiranes, the mole ratio of thediepoxide to the triphenol is 2:1. This adduct may be represented as##STR3## wherein T represents the triphenol nucleus and ##STR4##represents a moiety ##STR5## formed by adduction of a phenolic hydroxylwith one of the two oxiranes in a diepoxide molecule.

(Of course, in order to obtain a product by the method of the presentinvention in which a high proportion of the adduct molecules hadstructure (2), it would be necessary to employ a quite substantialexcess of the diepoxide and to separate that product, as by preparativechromatography, from the rest of the reaction mixture, which wouldconsist largely of unconverted epoxide and lower oligomers (seefollowing formulas).)

When a more practicable excess of the diepoxide is employed, some of theadduct molecules may be of structure (2) but a high proportion of themwill be oligomers having structures such as the following: ##STR6##etc., wherein -O-R-O- represents a moiety ##STR7## formed by adductionof phenolic hydroxyls with each of the oxirane groups in a diepoxidemolecule, and at least a few of the adducts should have structures suchas the following, in which all of the phenolic hydroxyls have beenreacted out: ##STR8## mole ratio epoxide to triphenol=(2n+3)/(n+1), and##STR9##

It will be apparent that adducts of the specified type in which the moleratio of diepoxide to triphenol exceeds 3:1 cannot exit.

Again, in order to prepare an epoxide (I) in which essentially all ofthe adduct molecules were of the structure (9), by the method of thepresent invention, one would have to employ a large excess of thediepoxide and "strain out" a fraction of the reaction mixture whereinthe adduct molecules would constitute the predominant component. This isparticularly so in view of the relatively low mobility and the sterichindrance which should be characteristic of the oligomeric products inwhich most of the phenolic hydroxyls have been reacted out.

It is to be noted that although the molecules required to constitute theessential component of the epoxide composition (I) must be derivablefrom adduction of a diepoxide with a triphenol, they may in fact havebeen produced in other ways. For example, the reaction product ofleucaurin with an excess of p-glycidyloxy, p'-allyloxy bisphenol A,followed by oxidation of the double bonds should yield an adduct of theforegoing structure (8). Similarly, oxidation of adducts of thetriphenols of formula (1) with diolefin monoxides should yield productsmeeting the foregoing specifications for the predominant component ofthe epoxide composition (I) of the present invention. Other types ofsynthetic routes to the specified predominant components may also befeasible.

EXAMPLES

The following examples are for purposes of illustration and are not tobe construed as limiting the scope of the present invention in a mannerinconsistent with the claims in this patent.

Example 1

Advancement of DER*-331 with 23 phr of1,1,1-tris(p-hydroxyphenyl)methane in the presence of ˜0.5 phr of A-1**catalyst.

0.5 Grams (0.5 phr) of A-1 catalyst (as 0.685 ml of a 70% solution inmethanol) was added with stirring to a melt of 100 grams (0.27 g. moles)of DER-331 and 18 grams (0.06 g. moles; 18 phr) of the trisphenol, themelt having been formed, without stirring, by heating the DER-331 to100° C., adding the trisphenol, heating to 120° C. and cooling back to100° C. Heating was continued to onset of an exotherm at 120° C. anduntil a temperature of 145° C. was reached, and then stopped. Theexotherm peaked at 160° C. and then the reaction mixture was allowed tocool slowly, then poured onto aluminum foil to solidify. The product hadan EEW of 354. No HDT (Heat Distortion Temperature) determination wasmade.

Example 2

Advancements of DER-331 with successively higher phr of1,1,1-tris(p-hydroxyphenyl)methane, using 0.05 phr of A-1 catalyst.

(a) 100 Grams (˜0.54 equiv., 0.27 moles) of DER-331 was heated to 100°C. in a 100 ml pyrex beaker. Addition of 18 grams (18 phr; ˜0.06 molesor 0.18 equiv.) of the trisphenol was commenced, with continued heating.To avoid sintering or gumming the reactants, stirring was delayed untila homogeneous, liquid solution formed--at a temperature of about 120° C.The solution, which was stirred thereafter, was cooled to about 90° C.and 0.05 grams (0.05 phr) A-1 catalyst was stirred in (as 0.069 ml of a70% solution in methanol, diluted with 3 ml of methanol). Heating wasdiscontinued at about 145° C. and a noticeable exotherm ensued at about160°, raising the temperature to a peak of about 180°. The reactionmixture was allowed to cool slowly, then poured out on a metal plate tosolidify (to a slightly soft resin mass).

The EEW of the resin was found to be 337 and the heat distortiontemperature (HDT) of a test bar (formulated with 100 phr of nadic methylanhydride and 1 phr of benzyl dimethyl amine and cured 2 hours at 90°C., 4 hours at 165° C. and 16 hours at 200° C.) was 177° C.

(b-d) Run a was essentially repeated but employing 21, 22 and 23 phr ofthe trisphenol, respectively. The corresponding exotherm ranges (onsetto peak) were 150°-220°, 160°-190° and 160° to above 190° and therespective EEW and HDT values were 375/165°, 410/162° and 418/ND (ND=notdetermined).

It was judged, from observation of the foregoing runs a-d, that attemptsto go to higher phr of the trisphenol would probably result in gelationof the hot reaction mass. This was confirmed in a run (e) in which 24phr of the trisphenol was employed. Considerable foaming was observedduring the exotherm (to a peak temperature in excess of 200° C.) and thereaction mixture became very viscous and distinctly rubber. The cooledproduct had an EEW of 578. No HDT test specimen was made.

It will be noted in comparing Examples 1 and 2a (both at 18 phr of thetrisphenol) that the EEW of the advancement product decreased from 354to 337 when the amount of catalyst was reduced from ˜0.5 to ˜0.05 phr.

Example 3

Advancement of DER-331 with 20 phr of1,1,1-tris(p-hydroxyphenyl)methane, using 0.048 phr of A-1 catalyst witha forced exotherm, rapid post-exotherm cooling to 140° C. and holding atthat temperature for 6 hours (to simulate holding for flaking) beforedetermining melt viscosity and sampling for preparation of an HDT testbar.

A one-liter resin kettle equipped with a mechanical stirrer, gas inletand outlet tubes, a thermometer and a thermo-controller probe, wascharged with 500 grams (2.69 moles; 5.38 equiv.) of DER-331 (which is aliquid) and 100 grams (0.35 moles; 1.026 equiv.; 20 phr) of thetrisphenol. The head-space in the kettle was swept with nitrogen and themixture heated, without agitation, to 120° C.--at which point stirringwas commenced. The mixture was stirred one hour at 120° C., then 343 mgof 70% A-1 catalyst in methanol (0.048 phr of A-1) was added and thestirring rate was increased. An exotherm started at 160° C. andsufficient extra heat was introduced to reach a peak temperature of 188°C.--at which point air-cooling of the kettle was used to bring thetemperature down to 140° C. in a relatively brief time (estimated atabout 20 minutes). The reaction mixture was then stirred slowly for 6hours with sufficient heating to hold the temperature at 140° C., thenpoured onto aluminum foil and allowed to cool and solidify. The producthad an EEW of 355 and a melt viscosity (RVA Brookfield) of 2100 cps at140° C.

Example 4

Advancement of DER-331 or DER-383* with different triphenol sourcematerials.

Three different triphenol source materials were utilized; (a) thetri(hydroxyphenyl)methane obtained from the acid catalyzed reaction ofortho-hydroxybenzaldehyde with phenol, (b) mixed triphenols derived fromReimer-Tieman waste bottoms, and (c) tris(p-hydroxyphenyl)methane.

A. Comparison between DGEBA/BA advanced resins and DER-331 advanced withtriphenol material (c).

Table I, following, presents a comparison between three resins (DER-661,-663U and -664U; U meaning uncatalyzed) prepared by advancing DER-331 inthe conventional manner with bisphenol A and four resins prepared byadvancing DER-331, in the manner of Example 3 herein, with the mixedtriphenols (c).

                  TABLE I                                                         ______________________________________                                        COMPARISON OF SOFTENING POINT AND                                             VISCOSITY FOR BIS A AND TRIS PHENOL RESINS                                                      Poly-   Phenolic                                                              phenol  Hydroxyl                                                                             Softening                                                                            Vis-                                  Resin     EEW     phr     phr    Point  cosity.sup.4                          ______________________________________                                        (1) DER-661   ˜525                                                                            31.5  0.28   70-80°                                                                        1020 Cs                                                                C..sup.1                                   (2) DER-663U  ˜750                                                                            39    .34    90-100°                                                                       2725                                (3) DER-664U  ˜925                                                                            43    .38    95-110°                                                                       6300                                (4) Tris.sup.3                                                                               347    18    .18    69°.sup.2                                                                     462                                 (5) Tris.sup.3                                                                               361    19    .20    79°                                                                           1057                                (6) Tris.sup.3                                                                               369    20    .21    81°                                                                           1490                                (7) Tris.sup.3                                                                               417    22    .23    89°                                                                           3651                                ______________________________________                                         .sup.1 Durran's Softening Point.                                              .sup.2 Mettler Dropping Point.                                                .sup.3 R.T. Waste Bottoms Tris Phenol.                                        .sup.4 Melt Viscosity at 150° C.                                  

It is evident from the data in Table I that non-sintering productshaving considerably lower EEW's and viscosities were obtained at muchlower polyphenol contents when the polyphenol was the triphenol mixture.

B. Table II, following, presents a comparison of resins made advancingan LER (liquid epoxy resin; DER-331 or -383) with successively higheramount of three different triphenol source materials (a, b, c). Exceptas noted, essentially the procedure of Example 3 was followed inpreparing the product resins.

                                      TABLE II                                    __________________________________________________________________________    COMPARISON OF TRIPHENOL-LER ADVANCED RESINS                                   Polyphenol/LER  phr TRIS                                                      System    Property                                                                            18    19    20 21 22 23  24  26 28 29                         __________________________________________________________________________    R.T. Waste                                                                              EEW   347   361   369   417                                         Bottoms Tri/                                                                  DER-331   VISC  462                                                                              Cs.sup.1                                                                         1057  1490  3651                                        OHB Tri.sup.3 /                                                                         EEW   337   365      396                                                                              410                                                                              418 GEL.sup.4                            DER-331                                                                       OHB Tri/  EEW         352      365                                                                              388                                                                              GEL.sup.4                                DER-383   VISC        845                                                                              Cs.sup.2                                                                            2766                                                                             3584                                        ppp Tris/ EEW   343         354              462                                                                              515                                                                              GEL.sup.4                  DER-383.sup.5                                                                           VISC  225                                                                              Cs.sup.2 288              1958                                                                             9600                          __________________________________________________________________________     .sup.1 Melt viscosity at 150° C. after 1 hr at 180° C.          .sup.2 Melt viscosity at 150° C. after return to 150° C.        .sup.3 Adduction carried out essentially in manner of Example 3, using        triphenol derived from ohydroxybenzaldehyde.                                  .sup.4 Reaction mixture gelled.                                               .sup.5 Exotherm not forced in preparation of this resin.                 

It will be seen from Table II that the character of the advancementproduct was not much effected by the differences between DER-331 and-383 or by the differences between the triphenols derived fromReimer-Tieman waste bottoms and orthohydroxybenzaldehyde. However, thetris(p-hydroxyphenyl)methane--which was both oligomer-free andisomer-pure, gave consistently lower melt viscosities at similar EEWvalues. The latter trisphenol also could be incorporated insubstantially greater amounts before gelling resulted.

C. Table III, following, presents the results of GPC (Gel PermeationChromatographic) analysis of three of the series of products listed inTable II, using a Waters Associates No. 501 Instrument and a series ofsix columns packed with controlled porosity beads of astyrene/divinylbenzene copolymer (MicroStyragel; registered tradename ofWaters Associates); the nominal pore sizes of the packings in thesuccessive columns--in Angstroms--were 100, 100, 500, 10³, 10⁴ and 10⁵.The carrier/eluting solvent, tetrahydrofuran (THF), was introduced tothe column train at a rate of 2 ml/minute. The computer normalized areapercents of each of six discernible peaks in the GPC scans are given inthe Table. Peaks 5 and 6 (the lowest molecular weight components, whichemerge last from the columns) were assigned--by comparison to authenticsamples of the individual materials--to the starting triphenols andLER's, respectively. The trisphenol (leucaurin) is actually lower inmolecular weight than the LER's but apparently associates strongly withTHF. It has a melting point well above 220° C. and complete dissolutionof it is difficult to effect, even at (unforced) peak exothermtemperatures.

It will be seen that advancement mixtures prepared in the manner ofExample 3 from diepoxide/triphenol mixtures comprising from about 18 toabout 22 phr of the triphenol may have a zero content of unconvertedtriphenol and contain from about 31 to about 24 area % (GPC) of theunconverted diepoxide.

                  TABLE III                                                       ______________________________________                                                   Tri                                                                           Phenol                                                             Triphenol/LER                                                                            Level,  GPC PEAK AREA                                              System     phr     1.sup.1                                                                              2    3     4   5.sup.2                                                                           6.sup.3                          ______________________________________                                        R.T. waste 18      14.5   31.4 17.8  5.5 --  30.8                             Tri/DER-331                                                                              18.5    21.3   27.5 16.8  5.3 --  29.1                                        19      19.8   29.1 17.3  5.3 --  28.5                                        20      23.9   28.1 16.9  5.0 --  26.1                                        22      26.9   28.8 15.1  4.3 --  24.9                             OHB Tri/   19      18.2   35.7 13.6  5.7 --  26.8                             DER-383    21      22.3   37.6 12.7  3.2 --  24.2                                        22      21.4   37.2 13.0  4.4 --  24.0                             ppp Tris/  19      --     43.2 21.0  4.7 6.5 24.6                             DER-383.sup.4                                                                            20      11.7   31.7 21.9  4.3 6.8 23.6                                        26      17.1   40.3 16.2  3.8 7.3 15.3                                        28      24.3   36.2 16.3  3.3 7.2 12.7                             ______________________________________                                         .sup.1 Highest MW peak.                                                       .sup.2 Free tri phenol peak.                                                  .sup.3 Free LER peak (DER331 or DER383).                                      .sup.4 Exotherm not forced in the preparation of this resin.             

It will be apparent, from Table III, to those knowledgeable in the art,that the molecular weight spread in triphenol advanced LER's isconsiderably greater than in conventional, bisphenol advanced LER's.Both the level of unconverted LER and the contribution of highermolecular weight species are relatively larger in the advancementproducts of the present invention. It is particularly interesting tonote the presence of substantial amounts of the unconverted tris phenolin the last four resins in the Table; this is attributed to not havingforced the exotherm in preparing the subject resin. It may also be notedthat the unconverted trisphenol could be utilized as at least part ofthe curing agent for the subject resin; it is a proven phenolic curingagent for epoxides.

D. Table IV, following, provides a comparison of HDT's for the fourresins of the invention listed in Table II, with each other and with anHDT for a commercial "epoxidized" cresol novolac, ECN-1280 (registeredtradename of Ciba-Geigy Co.).

                                      TABLE IV                                    __________________________________________________________________________    HEAT DISTORTION TEMPERATURE DATA FOR TRIS PHENOL-                             ADVANCED EPOXY RESINS                                                         Tris        Curing Agent HDT.sup.1                                            Resin Phenol          Tris 3.2  438                                           System                                                                              Level, phr                                                                          NMA.sup.5                                                                          MDA.sup.6                                                                          Phenol.sup.7                                                                       Novolac.sup.8                                                                      Novolac.sup.9                                 __________________________________________________________________________    OHB.sup.2 /                                                                         18    --   161  157  137                                                DER-331                                                                             19    167  140  140  136                                                      21    164  148  150  142                                                      22    162  147  --   136                                                R.T. Waste                                                                          16    133  --   --   --   --                                            Triphenol/                                                                          19    112  --   --   --   150                                           DER-331                                                                             22    141  --   --   --   --                                            OHB.sup.3 /                                                                         19    139  --   --   --   --                                            DER-383                                                                             21    145  --   --   --   --                                                  22    142  --   --   --   --                                            ppp Tris.sup.4                                                                      20    125  --   --   --   --                                            DER-383                                                                             26    122  --   --   --   --                                            ECN-1280                                                                            --    .sup. 189.sup.5                                                                    --   --   --   --                                            __________________________________________________________________________     .sup.1 HDT for 1:1 cured system; determined with duPont 99 TA.                ThermoMechanical Analyzer; which generally gives HDT's about 10°       lower than the "classical" method.                                            .sup.2 Material (a) above. Cure schedule 2 hrs/100° C., 18             hrs/180° C., 2 hrs/200° C.                                      .sup.3 Material (b) above. Cure schedule 2 hrs/100° C., 18             hrs/180° C.                                                            .sup.4 Material (c) above. Cure schedule 2 hrs/100° C., 18             hrs/180° C.                                                            .sup.5 Typical value for ECN1280 at 0.85 stoichiometry.                       .sup.6 Nadic Methyl Anhydride.                                                .sup.7 Methylene Di Aniline.                                                  .sup.8 Tris(phydroxyphenyl)methane.                                           .sup.9 A 3.2 functionality φOH/HCHO condensate.                           .sup.10 Dow Epoxy Novolac 438. ˜4 functionality φOH/HCO             condensate.                                                              

It will be seen from the data in the Table that the HDT's of theadvancement products of the present invention fall between those(˜100°-120° C.) typical of DGEBA/BA advancement products and those(160°+) typical of epoxidized condensation products of cresols andformaldehyde, such as ECN-1280. The somewhat lower HDT's for thetrisphenol/DER-383 advancement product are believed due to not all ofthe tris phenol having been reacted into the resin; relatively higherHDT's would be expected with phenolic curing agents, rather than NMA.

Example 5

Blends of separately formed adduction products of LER's with bis- andtriphenols, vis-a-vis co-adduction products of bis- and triphenols withthe LER's.

Table V, following, is a compilation of property data for epoxides (I)of the present invention prepared by two different methods from DER-331,bisphenol A and tris(p-hydroxyphenyl)methane. The resins designated as Athrough E in the Table were made--essentially in the manner of Example3--by co-adducting the bis- and trisphenols in several differentproportions with DER-331. The resins designated as A', B' and C' weremade by blending separately formed adducts of the bis- and trisphenolswith DER-331.

                                      TABLE V                                     __________________________________________________________________________    COMPARISON OF LER COADDUCTS OF TRIS PHENOL AND BIS A                          WITH BLENDS OF LER'S SEPARATELY ADVANCED WITH THE                             TRIS- AND BISPHENOLS                                                          __________________________________________________________________________    Co-Adducts                                                                                Wt. %                                                             Designa-                                                                            Wt. % Bis  Wt. %                                                        tion  DER-331                                                                             A    Tris EEW  VISC.sup.1                                                                            DP.sup.2                                                                             HDT.sup.3                           __________________________________________________________________________    A     75    15   10   454  555 Cs  76.7° C.                                                                      130° C.                      B     75    20    5   611  2605    93.8   111                                 C     80    10   10   440  490     --     124                                 .sup. D.sup.4                                                                       85     0   15   350  589     69.2   145                                 E     75    10   15        Gelled                                             __________________________________________________________________________    BLENDS                                                                            Tris/    Bis A/                                                           Desig-                                                                            331   Wt.                                                                              331       % EQ..sup.5                                                                        % EQ..sup.5                                                                        % EQ..sup.5                                  nation                                                                            Adv. Resin                                                                          %  Adv. Resin                                                                          Wt. %                                                                             331  Bis A                                                                              Tris VISC.sup.1                                                                         HDT.sup.3                          __________________________________________________________________________    A'  22 phr                                                                               50                                                                              664U  50  76   15   9    4559                                                                             Cs                                                                              112° C.                     B'  22 phr                                                                              33 664U  67  74   20   6    4918 106                                C'  22 phr                                                                              57 661   43  80   10   10   1906                                                                             121                                  __________________________________________________________________________     .sup.1 Viscosity at 150° C. in Cs on Brookfield RVT viscometer.        .sup.2 Mettler dropping point.                                                .sup.3 Heat distortion temperature by TMA on sample cured at 1:1 with         nadic methyl anhydride on cure schedule 2 hrs/100° C., 18              hrs/180° C.                                                            .sup.4 Only nominally a "coadduct; included for comparison.                   .sup.5 (Equivalent ratio of component to all components) × 100.    

It will be seen from the Table that the co-adducts had substantiallyhigher HDT's and considerably lower melt viscosities than comparableblends. Also, if allowance is made for the higher total phenolichydroxyl content in run A vs. run c, the HDT's in both series increasedas the trisphenol to bisphenol ratio went up.

Resin D (no bisphenol) had a high enough softening point to benon-sintering and was distinctly superior as to EEW, melt viscosity andHDT. It is evident that binary trisphenol/DER-331 advancement productscomprising as little as 15 weight % (about 18 phr of the trisphenol havea highly desirable combination of EEW, melt viscosity, softening pointand HDT values. Diepoxides having the compositions of DER-383 andDER-332 (essentially pure, monomeric DGEBA) are considered essentiallyequivalent to DER-331 for the preparation of such advancement products;see the data for the last resin (DER-383-derived) in Table II, forexample.

The latter trisphenol, tris(p-hydroxyphenyl)methane is particularlyadvantageous as the triphenol in the epoxide compositions (I) of theinvention by reason of conferring minimal viscosities and being usablein amounts of up to 28 phr without causing the adduction mass to gel.

As an example of advancement catalyst other than "A-1", BTMAC-benzyl,trimethyl ammonium chloride--may be mentioned. (This catalyst may bepresent in residual amounts in some LER's). It is less selective forphenolic hydroxyls over alcoholic hydroxyls than is desirable but may beused.

The utility of the epoxide compositions of the present invention is notlimited to molding or casting resins. They may also be employed inpowder coatings, in adhesives, laminates, resin-modified concretes,etc., as such or in admixture with conventionally employed materialssuch as reactive diluents and/or the full range of known additives forepoxies.

For all applications, the epoxide composition may be sintering ornon-sintering but preferably is non-sintering.

What is claimed is:
 1. An epoxide having an average oxiranefunctionality of about 2 or more and comprising at least 5 weight % ofoligomeric molecules each of which is a reaction product of a diepoxidehaving an EEW of about 300 or less with a 1,1,1-tri(hydroxyphenyl)alkaneor -alkene wherein the alkane or alkene moiety contains from 1 to 11carbons, the mole ratio of said diepoxide to said triphenol, in each ofsaid molecules, being--independently--within the range of from 2:2 to3:1.
 2. An epoxide according to claim 1 which is the reaction product ofa liquid epoxy resin with from about 16 to about 28 phr of saidtriphenol in the presence of an advancement catalyst.
 3. An epoxideaccording to claim 2 which is non-sintering and is the product of thereaction of said resin with from about 18 to about 28 phr of saidtriphenol.
 4. An epoxide according to claim 3, said triphenol being atris(p-hydroxyphenyl)alkane as defined in claim
 1. 5. An epoxideaccording to claim 4, said trisphenol beingtris(p-hydroxyphenyl)methane.
 6. An epoxide according to claim 3, saidtriphenol being other than a tris(p-hydroxyphenyl)alkane or alkene andhaving been reacted with said resin in the amount of from about 18 toabout 24 phr.
 7. An epoxide of claim 1 consisting essentially of saidoligomeric molecules.
 8. An epoxide according to claim 2, said liquidepoxy consisting at least predominantly of molecules of the formula##STR10## wherein n is within the range of from 0 to about 0.15 andoptionally including a minor proportion of molecules derivable, byoxirane hydrolysis, from molecules of the latter formula.
 9. An epoxideaccording to claim 8, the liquid epoxy being derived, by partialhydrolysis, from molecules of said formula having an average n value ofabout 0.15.